1. Field of the Invention
The present invention relates to a video tape recorder, and more particularly, to a frequency modulation (FM) recording apparatus for recording FM-modulated video signals to video tapes.
2. Description of the Related Art
A video tape recorder performs frequency modulation upon a video signal and then records the frequency modulated video signal. In a double-deck video tape recorder, a signal reproduced in one deck can be recorded in the other deck. In this case, an FM signal reproduced by a header in one deck (henceforth to be referred to as a Playback (PB)-FM signal) is pre-processed and supplied to the other deck. Here, pre-processing involves image enhancement equalizing of the playback frequency modulated signal.
The frequency modulation recording device of a video tape recorder receives a PB-FM signal and generates a recording FM signal (REC-FM signal). The REC-FM signal is recorded after passing through an equalizer and a recording header.
The recording device has a drawback in that the apparatus cannot properly compensate for an imbalance between channels. That is, if there is a difference in the response characteristics of the header of one channel and the header of a second channel, the levels of the signals they reproduce respectively, will be uneven. In addition, there is a problem of noise flowing into the REC-FM signal through the processing steps of the PB-FM signals.
Exemplars of the art, U.S. Pat. No. 5,552,895 for Double-deck Magnetic Recording/Reproducing Apparatus by Kim, U.S. Pat. No. 4,641,206 for Video Signal Recording and Reproducing Apparatus Including a Noise Reduction Circuit issued to Iwafune, U.S. Pat. No. 5,075,803 for Signal Discriminating Device for VTR having Expanded Dynamic Range issued to Moro, et al., U.S. Pat. No. 5,194,963 for Dual Deck Videocassette Recorder System issued to Dunlap, et al., U.S. Patent RE36,339 for Circuit for Tape Duplication in Video Tape Recorder issued to Yun, et al., U.S. Pat. No. 3,947,873 for Method and Circuit for Detecting and Compensating for Drop-out and Distortion of Frequency Modulated Video Signals issued to Buchan, U.S. Pat. No. 5,034,823 for Drop-out Compensation Circuit issued to Geerlings disclose frequency modulated video recording circuits. I have noticed that the art does not show a frequency modulated video recorder that can control the video channel balance while reducing noise in order to provide a high fidelity recording.